Fatty acid profiles of olive oil and moringa oil and their influence on nanoemulsion formation via D-phase emulsification using bakuchiol as a model active compound

Abstract

Moringa oil (MO) and olive oil (OV) share similar chemical compositions, often considered interchangeable in various applications. However, their behavior in nanoemulsion formation, a widely-used process in the cosmetic industry, remains relatively unexplored. This study aimed to investigate their fatty acid compositions and how they respond to nanoemulsion formation using the D-phase emulsification method. MO comprises approximately 79% oleic acid, 7% palmitic acid, 6% stearic acid, and other minor components. In contrast, OV contains roughly 70% oleic acid, 14% palmitic acid, 10% linoleic acid, and other constituents. In the context of nanoemulsion formation, both oils exhibited similar trends in particle size, polydispersity index (PDI), and zeta potential when varying the formulation compositions. The type of oil significantly influenced particle size at low surfactant concentrations and PDI at higher oil concentrations, consistently affecting zeta potential. The optimal formulation, O1T15G5, yielded droplet sizes of approximately 222 nm (MO) and 50 nm (OV). Both MO and OV nanoemulsions responded similarly to the substitution of oil with bakuchiol (BK), with O0.7B0.3T15G5 achieving the smallest spherical particle size confirmed by TEM and DLS analysis. Encapsulation efficiency and antioxidant activity remained largely unaffected by types of oil. Stability tests at different temperatures showed some distinctions in physical stability but similarities in antioxidant activity stability. The types of oil did not significantly impact BK release or cytotoxicity levels. This research underscores the potential utility of MO as a viable alternative to OV in cosmetic applications, shedding light on their similarities and performance within nanoemulsion formulations.